Mema,
You mentioned being 79 years old and FYI being over the age of 65 is a risk factor in sleep apnea:
https://en.m.wikipedia.org/wiki/Sleep_apnea
A sleep study would quickly diagnose any sleep disorder you have and if this situation persists I would recommend it. The usual treatments are to either lose weight or use the CPAP machines or both. When I was diagnosed in 2010 they gave me a machine which kind of sucked and I got rid of it, but I have heard the newer machines are more comfortable and less noisy.